The next round of bitter cold was expected to hit the southern United States on Tuesday after the first severe winter storm of the year inundated much of the country with ice, snow and wind.

The massive storm system caused disruption even in areas of the country that are normally spared from winter’s wrath. Trees fell in some southern states, a freeze threatened in Florida, and in Dallas people searched deep in their closets for hats and gloves.

Wind-chilled temperatures could drop into the teens to lows of minus 20 degrees (as low as minus 10.5 degrees Celsius) from Texas to the Gulf Coast by early Tuesday, according to the National Weather Service. A low pressure area is then expected to form near South Texas as early as Wednesday, bringing potential snowfall to parts of the state, including Dallas, as well as to Oklahoma, Arkansas and Louisiana.

The polar vortex that dipped south over the weekend held icy grip on much of the country east of the Rocky Mountains on Monday, making many roads treacherous, forcing school closures and causing widespread power outages and flight cancellations.

Ice and snow covered major roads in Kansas, western Nebraska and parts of Indiana, where the National Guard was deployed to help stranded motorists. The National Weather Service issued winter storm warnings for Kansas and Missouri, where blizzards brought wind gusts of up to 45 mph (72 km/h). The warnings extended into New Jersey into early Tuesday.

A Kentucky rest stop just outside Cincinnati was crowded Monday with large trucks moving down an icy and snow-covered Interstate 75. Michael Taylor, a long-haul driver from Los Angeles who was hauling a load of carpets to Georgia, said he saw numerous cars and trucks stuck in ditches and struggling with iced-up windshield wipers before pulling off the highway.

“It was too dangerous. I didn’t want to kill myself or anyone else,” he said.

The polar vortex of ultra-cold air usually revolves around the North Pole, but sometimes it plunges south into the United States, Europe and Asia. Studies show that a rapidly warming Arctic is partly responsible for the increasing frequency of the polar vortex, which is expanding its influence.

Temperatures are falling across the country

The eastern two-thirds of the U.S. struggled with bitter cold and wind chill on Monday, with temperatures well below normal in some areas.

A cold weather warning will go into effect along the Gulf Coast early Tuesday. In the Texas capital Austin and surrounding cities, wind temperatures could drop to as low as 15 degrees (minus 9.4 °C).

Several cold days were expected in the northeast.

Transportation was difficult

Hundreds of car crashes have been reported in Virginia, Indiana, Kansas and Kentucky, where a state trooper was treated for non-life-threatening injuries after his patrol car was struck.

Virginia State Police responded to at least 430 crashes on Sunday and Monday, including one that resulted in a fatality. According to police, additional weather-related fatal accidents occurred on Sunday near Charleston, West Virginia, and on Monday in Winston-Salem, North Carolina. There were two fatal accidents in Kansas over the weekend.

As of Monday evening, more than 2,300 flights had been canceled and at least 9,100 more delayed across the country, according to tracking platform FlightAware. Ronald Reagan Washington National Airport reported that about 58% of arrivals and 70% of departures were canceled.

A record 8 inches (more than 20 centimeters) of snow fell at Cincinnati/Northern Kentucky International Airport on Sunday, leading to dozens of flight cancellations that continued into Monday. About 4 inches (about 10 centimeters) fell Monday in the Cincinnati area, where car and truck crashes blocked at least two major roads into downtown.

More snow and ice is expected

In Indiana, sections of Interstate 64, Interstate 69 and U.S. Route 41 were covered in snow, prompting authorities to ask people to stay home.

“It’s snowing so hard, the snowplows go through and within half an hour the roads are completely covered again,” said the state police commander. Todd Ringle said.

An additional 6 to 12 inches (15 to 30 centimeters) of snow was forecast for the Mid-Atlantic region on Monday. Dangerously cold temperatures were expected, with overnight lows falling into the single digits (below minus 12.7 C) by midweek across the Central Plains and the Mississippi and Ohio valleys.

North Texas was expected to see 2 to 5 inches (about 5 to 13 centimeters) of snow starting Thursday, according to the National Weather Service. Snow could also fall in Oklahoma and Arkansas, with some parts possibly seeing more than 4 inches (about 10 centimeters).

Classes have been canceled in several states

School closures have been widespread, with districts in Indiana, Virginia, Kentucky, Missouri and Kansas canceling or delaying the start of classes on Monday. Among them was Jefferson County Public Schools in Kentucky, which canceled classes and other school activities for its nearly 100,000 students.

Classes were also canceled in Maryland, where Gov. Wes Moore declared a state of emergency on Sunday and announced that the state’s government offices would also remain closed on Monday. Government offices were also closed Monday in Kentucky, where Gov. Andy Beshear declared a state of emergency.

Tens of thousands are without electricity

Many were left in the dark as temperatures dropped. More than 218,000 customers were without power in Kentucky, Indiana, Virginia, West Virginia, Illinois, Missouri and North Carolina as of Monday evening, according to utility tracking website PowerOutage.us.

In Virginia’s capital, a power outage caused a temporary disruption in the water system, officials said Monday afternoon. Richmond officials urged residents of the city of more than 200,000 not to drink tap water or wash dishes without first boiling the water. The city also urged people to conserve water, for example by taking shorter showers.

City officials said they were working nonstop to get the system back online.

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Whittle reported from Portland, Maine. Associated Press journalists Bruce Schreiner in Shelbyville, Kentucky; Dylan Lovan in Louisville, Kentucky; Ben Finley in Norfolk, Virginia; Lea Skene in Baltimore; Kathy McCormack in Concord, New Hampshire; Julie Walker in New York; Sophia Tareen in Chicago; Kimberly Chandler in Montgomery, Alabama; Zeke Miller in Washington, D.C.; John Raby in Charleston, West Virginia; Summer Ballentine in Columbia, Missouri; and Hallie Golden in Seattle contributed.

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